Telephone-transmitter.



o mitter;

ITE STATES,

PATENT' Fries.

ELLIS F. FROS'1`,.OF THE UNITED STATES ARMY.

TELEPHONE-TRANSMITTER.

SPECIFICATION forming part' of Letters Patent No. 637,453, dated November 21, 1899.

` Application filed August 19, 1899.

Tou/ZZ whom it may concern/ 4 Beit known that I, ELLIS F. Faosr, of the United States Army, rosidin g at Vtashington, in the District of Columbia, have invented 5 certain new and useful Improvementsin Telephone-Transmitters and I do declare the fol; lowing tbe a full, clear, and exact descrip-v tion of the-invention, such as will enable otl1 ers skilled in the art' to which it appertains xo to make and use the same, reference being had to the accompanying drawings, and to the iigures of reference marked thereon, which form apart of this specification. S

My invention relates to telephone n1icro i 5 phone-transmitters.

The oiiect of my invention is to produce a telephonei-transmitter possessing all the resonantand sensitive qualities of lthe Blake transmit r type combined with the desirable qualities of the transmitters of the Hunning transmitter type. l

It is also one object to produce a telephonetransmitter which will completely avoid the ,packing of the Hunnin'g type of instru-v ments. y Another Objectis to produce an instrument of great simplicity, ease, and cheapness ot'V manufacture, ease of assemblage, and great durability.

My invention consists of such a combina-j tionof electrodes and granular conducting --material with a chamber, diaphragm, and cas- -ing as to accomplish the above results.

a suitable casing in which is formed the 'speaking orifice, of a diaphragm mounted therein,which diaphragm carries an electrode, of a chambered block to surround this electrode and-clamp the diaphragm; also, of a secondelectrode in said chamber, but'not in contact with the first electrode, .yet whose surface opposed to the iirst electrode is not parallel to the opposed surface' thereof, of a granular conductor between said electrodes, and of means foi-'assembling said parts.

The following is a description of myinvention, in which reference is made to the accompanying' drawings.

Figure 1 isla vertical section of my trans- My invention consists more particularly of 4oriiice, as in Fig. 4.

Fig. 2 is an elevation with portions Serial No. 727.825. .flic model.)

broken away. Fig. 3 is a detail in perspective of the back electrode. Fig. 4 is a modification showing the same construct-ion, but involving electrodes mounted ou two separate diaphragms, the diaphragme leading to a ,common speaking-orifice.

. the diaphragm 4 a disk of cond ucting material 5, .as carbon, is mounted by means of a metallic stud 6. A block 7 is bored so as to form a shoulder 8 to rest against the diaphragm 4'and yet leave a vibration-chamber 9, so as to form a chamber 10 to receive a felt ring 11, also so as to form the chamber 12. The inner diameter of the felt ring 11 and the Ch'imber 12 are the same. When the block 7 is in place, its shoulder 8 clamps the diaphragm 4 against the shoulder4 2 of the case and brings the electrode 5 in the felt ring 11. Also in the chamber 12 is a back electrode 13, but whose surface oppositethe electrode 5 isinclined away from the perpendicw. lar upward, as shown in Fig. 1.. Between the electrodes 5 and 13 a granular conducting material 14, as carbon, is placed'to electrically connect the two electrodes. A backboard 15 is screwed on the case 1 and serves to clamp the whole together.

Suitable conducting-wires, one, 16, from the diaphragm and the other, 17, from the back electrode 13, are led to binding-posts on the back-board.

Obvious modifications of this construction are clearly within the scope of this invention. For instance, the front or diaphragm electrode 5 may be beveled and the back one, 13, pervpendicular, or both may be beveled, but in both diaphragme lead to a com mon speaking- It is essential to the attainment of the ob- `)nets of myinvention that the surfaces of the electrodes be non-parallel and that each beveled surface be inclined from the-perpendicuroo It is clear,A by reason of the foregoing construction andarrangement 4of t-he several parts as shown inFig. 1,.that the direction of 'pressure of the frontelectrode 5 against the granular condnctor 14 willbe atrig'ht .an-

gles to the planeet the diaphragm, and also that this direction ofv pressure after being transmitted throughthe granular conductor to the inclined face of the back electrode will be turned through an angle bythe said. i'-

clined face, thus discharging the pressnrefof the vibratory electrode at an'angle to'the di. rection of vibration of the vibratory electrede. l l

It is clear, by .reason of the foregoing construction and arrangement of the several parts as shown in Fig. 4, that the direction of 'pressure of the-electrodes 5 gainstthe granular conductor 14 is discharged at an angle to the direction of vibration of these vi-l bratory electrodes becauseof the inclined surfaces of the electrodes `5.

Having thus. described my invention, I claimv 1.' In a telephone-transmitter, the combinatien with a diaphragm, an electrodey mounted eer-,45e

'and an electrode therein inclined tothe 1`1rst, 'of a granular conductor partially filling said chamber and between said electrodes.

2. In a telephone-transmitter, the combina# tion with a diaphragm, a chamber inclosin-g electrodes of non-parallel opposed surfaces, of a granular conductor partial-ly filling said chamber -and.between said electrodes, and

means for .enabling the vibrations. of the daphragm to disturb the granular conductor.

3. I-n a telephone-transmitter, the combination with a diaphragm, electrodes of opposed non-parallelsurfaces oneor both inclined to the direction of vibration, and a chamber inclosing' said electrodes, of a granular conductor .partially filling said chamber and between said electrodes.

4. In a granular telephone transmitter, means for directing the pressure ol. the vibralf eryelectrode against the granular conductor and means for dischargingsaid pressure at an angle to the direction of vibration of the vibratory electrode.

In testimony whereof Iaix my signature in presence -of two witnesses.

ELLIS F. F-ROST.

, Witnesses: HOWARD W. SHUsrER,

thereon, a'chamber inclosing said electrode,

THOMAS BRADLEY.

It Iis hereby certified that the residence of the patentee in the grant and in the printed slpeciczttion of Letters Patent No. 637,453, grnted'Nvember 21,1899, upon the application of.E,11 is 1F. Frost, for an improvement in Telephone-'IQratnsmitters, were errnieously Writtenand printed United -States Anny, Whereas said residenoe should have been ,Written and printed Wqs1.rpgton-,'Dstrct ofolumia; and that. the said Letters Patent should be read with this correctionutherein that the same may conform tothe record of the leaseixx the Patent iee.

Signed, houn'tersigned, end sealeciths 28th day of November A, D., '1899.

[SEAL] ,WEBSTER DAVIS,-

" Assistant. Secretary of the Infarto-r.; v

Couutersigned C. H. DUELL,

v Commissioner of Patellis. 

